This invention relates to ignition cable assemblies and more specifically to ignition cable assemblies that have a terminal attached to the end of the ignition cable and encased within a flexible elastomeric nipple or boot that provides the primary environmental seal and dielectric insulation for the terminal when it is connected to a mating terminal.
One known method of extending the dielectric capability of such an ignition cable assembly involves the use of a close fitting insulation sleeve. The sleeve is manufactured as a separate part of rigid, dielectric insulator material such as polyester, and inserted into the elastomeric boot. When inserted, this sleeve insulates a substantial portion of the terminal inside the elastomeric boot so that the dielectric arc over distance to ground is significantly increased when the ignition cable terminal is connected to a coil, distributor or spark plug, particularly when the mating terminal is located in a female insulating tower. The resulting increased dielectric capability increases long term reliability.
While this method does improve reliability, nevertheless, this method has several drawbacks. The manufacture of a separate insert sleeve adds cost and complexity to the manufacturing process. Moreover, automated assembly is limited to straight cable assemblies having straight terminals and a straight cable dress whereas an angled terminal and/or an angled cable dress is needed or desired in many ignition cable assembly applications. Furthermore, interior space limitations of the elastomeric boot require tight manufacturing tolerances for the plastic sleeve that are difficult to maintain.